1. Field of the Invention
The subject invention is generally related to modular systems for work functions on a drilling or production rig or platform and is specifically directed to the composition, operation, and performance of a skid based modular system for coiled tubing and similar operations.
2. Discussion of the Prior Art
Various operations are routinely performed on drilling and production platforms. Each of the operations includes subsets of equipment and specific operational functions associated with the equipment. By way of example, a coiled tubing operation includes a plurality of different processes or sequences of actions, some of which can be viewed as general to the service and some of which can be viewed as specific to the particular system used. The general process components include positioning equipment on the platform, assembling the equipment, stabbing tubing, pressure testing well control equipment and similar functions incorporated regardless of the specific equipment used. Specific functions are dictated by the particular equipment and system being utilized.
The deployment of coiled tubing pressure control and conveyance equipment in offshore environments is a time consuming process made complicated by spatial constraints, crane lifting limitations, safety considerations and intensive assembly on location. The majority of coiled tubing systems utilized offshore to date incorporate virtually no pre-assembly of system components making the Rig Up process extremely inefficient. This is particularly true for systems utilizing the multiple pressure control components required to perform high pressure work.
A constant in all systems is the requirement that the various components of the system be moved into place, assembled and tested prior to initiation of the operation. In the industry, this is generally referred to as “Rig Up” work. The amount of time and expense involved in Rig Up work is substantial and dramatic increases in profitability of the rig can be achieved with small time savings in repetitive Rig Up operations.
Very little integration of conveyance and pressure control equipment is currently utilized offshore. Coiled tubing jacking frames are currently used in offshore environments to support and manipulate coiled tubing conveyance equipment. The typical CT jacking frame consists of a four-post support system containing a one or two-dimensional in-plane translation type table into which the injector is inserted. The injector support can also be raised or lowered. One type of system also possesses a rotation table for aligning the injector gooseneck with the reel. Due to spatial transport restriction, the injector and jacking frame are transported separately onto the platform. Pressure control equipment including BOPs, riser sections and strippers are separately lifted into appropriate positions in the well stack. In the prior art systems, a minimum of seven components must be separately installed on location.
The principal hindrance in the Rig Up of existing coiled tubing systems is the need to assemble virtually every component in the system on location. This fragmentation of the operation results in numerous crane lifts to move equipment components into position and numerous assembly steps to couple these components together.
A major drawback to pre-rigging or assembly prior to Rig Up is the sheer size of the equipment being utilized. In order to achieve maximum benefit by pre-assembly the equipment must fit reasonable transportation dimensions.
To date, there are not any available systems that permit comprehensive pre-rigging at an offsite location. It is desirable that such a system be developed for increasing safety by eliminating repeated make-up and break-down of critical assemblies, and by permitting increased efficiency in installing such systems for operation. It is also desirable that such a system be developed to permit transport to and from a rig in standard transport systems and containers in its assembled state.